Grinding fixture for single point tools



.Fume E?, 1952 J. J. SANDERS GRINDING FIXTURE FOR SINGLE POINT TooLs 2SHEETS-SHEET l Filed Jan. 18, 1951 Mmmm.

INVENTOR. JOSEPH J. SANDERS. BY M @.d/w'oma/w ATTOR N EYS.

im 17, J, J, SANDERS v GRTNDING FIXTURE FOR SINGLE POINT TOOLS FiledJan. i8, 1951 2 SHEETS- SHEET 2 (25 6'/62 6 ,3 7U sa@ 5355 35 48 7L 27/33 INVENTOR.

JOSEPH J. SANDERS. BY

ATTO R N EY S.

Patented June 17, 1952 GRINDING FIXTURE FOR SINGLE POINT TOOLS Joseph J.Sanders, Philadelphia, Pa.

Application January 18, 1951, Serial No. 206,701

(Granted under the act of March 3, 1883, as amended April 30, 1928; 3700. G. 757) 2 Claims.

The invention described herein may be manufactured and used by or forthe Government for governmental purposes without the payment to me ofany royalty thereon.

My invention relates broadly to the art of grinding. Although notlimited solely thereto, it has particular reference to the grindingofsingle point cutting tools of the type used on lathes, screw machines,planers, Shapers, and other similar machines.

Single point cutting tools for such machines often consist of a metallicshank, square or rectangular in cross section, one end of which isshaped by grinding to form a cutting edge. The cutting edge, as viewedfrom above, generally is composed of two straight sides formed at anoblique angle to each other and connected by a radius. From eachstraight side, a flat surface issues and continues to the lowerextremity of the tool as does the radius. The at surfaces. like the twostraight sides, are inclined toward each other from top to bottom; andeach forms an obtuse angle in relation to the bottom of the tool. Theshape of the cutting edge and the slope of its angles depend upon jobrequirements.

In order to grind such a cutting edge, it is necessary to position thetool at a compound angle `(i. e. tilted in relation to the truehorizontal and the true vertical) and then, while maintaining thecompound angle, simultaneously to impart a combination of rotary andlinear motions to the tool in relation to an abrasive wheel. Therefore,it is obvious that the type of grinding to which the present inventionhas reference is not of the ordinary profile or fiat surface varieties.

'Ilhose skilled in the art realize that the dictates of mass productionand interchangeable manufacturing technique in such extensive use todayrequire that the tools themselves used in producing products be alsomass produced and interchangeable. This is especially true in relationto shaped cutting tools of the type to be discussed in thisspecification.

Before my invention such grinding of single point tools was done invarious ways which, for one reason or another, lacked the desired easeand economy of operation. One primordial technique was manually to holdand guide the tool against a revolving abrasive wheel, but this isadmittedly very hazardous, ineiiicient, and inconsistent in result.

A later method of doing this type of grinding consisted of rigidlymounting the tool upon the table of a grinding machine so that one iiatsurface could be ground. In order to grind the second iiat surface, theset-up had to be changed. or another machine had to be used. Then theradius connecting the two surfaces had to be ground by manually holdingand guiding the tool against another grinding wheel.` Obviously, themultiple setting-up of one machine, or the use of two separate machines,was costly and time consuming. Further disadvantage of this method wasthe final radius-grinding by manual guidance. Even with the use ofgrinding templets, a further hindrance, the results were inadequate andthe process inemcient.

The art is rich with Ways and means of grinding profiles on cylindricaland iiat workpieces; but the proper grinding of a single point cuttingtool of the type here discussed, in order to retain tool strength and toobtain maximum cutting eiiciency, requires more than the forming of aprofile. Best results in grinding single point cutting tools areobtained by using the face of an abrasive wheel rather than itsperiphery and, until the advent of my inventive iixture, the art lackedany single means of accomplishing the proper grinding of single pointtools with but one set-up of the workpiece.

Although the shapes and sizes of cutting edges on single point tools aremany and varied, I shall illustratively discuss the grinding of acutting edge requiring compound angular setting of my grinding fixture.However, such compound angular setting may not always be required. Insuch cases the grinding process is further simplified.

In practicing my invention I provide a fixture which is easily attachedto the work table of any simple grinding machine. The fixture consistsof a base plate upon which is pivotally mounted an angle plate. Thisarrangement permits the angle plate to `be set parallel or at aninclination to the base plate.

Slidably and rotatably engaged to the angle plate is a slide plate uponwhich are mounted a vise base and a template. The vise base is arcuatelygrooved parallel to the pivotal mounting between the base and angleplate in order adjustably to accommodate a vise block for holding thetool to be ground. This vise block can be set at an angle to the visebase. The combination of the available angular setting between the visebase and the vise block, and the angular setting possible between thebase plate and the angle plate, makes the iixture capable of compoundangle adjustment. A portion of the template is shaped to correspond tothe .cutting edge of= the tool to be ground, but the shape on thetemplate is considerably enlarged over that required to be ground uponthe tool. The shaped edge of the template is constantly urged by springpressure against a stop bar which is se cured to the angle plate.

By oscillation of an operating handle secured to the vise base, the toolto be ground is moved up and back past the machines grinding wheel.Depending upon the shape of the template, the vice block containing thetool is also capable of linearly advancing or withdrawing from thegrinding wheel as the tool is oscillated, yso 'that the templatesprofile is imparted, in reduced size, to the tool being ground. Theavailable compound angular setting of the vise block vprovides theproper grinding of the two flat surfaces danking the rounded point.

One object of my invention is `to provide a compact tool grinding xture,comparatively small `in relation to grinding machines, 'which is capableof simultaneous compound angular adjustment and 'separate or combinedcurvilinear or rectilinear .movement -Another object is to provide 'agrinding ix- .turerwhich can be used `on the x.most simple type-ofgrinding machine.

4.Afurther object is to ',provide'afgrinding xture which -will eliminatethe necessity for vmultiple set-:upsof .a'single machine-or 'the neediormore than one grinding machine informing desired profiles Yon cuttingtools.

The foregoing and other vobjects and advantages of my invention -will'become apparent from fan vinspection of the following description andthe accompanying drawings, wherein:

Fig. `1 :is atop View of my inventive xture, partly .in section andpartly broken away, secured 'tothe worktable of a small surface'grindingmachine, orthelike. The too'lto beground is'shown abutting the"ixturesgaging armas is necessary preceding the grinding operation. Forsimplicity of drawing, no angular adjustments of the fiixturearefshown;

kFig. Zlis .a `side viewfas seen from line 2-2 of Fig. 1, but theiixtures gaging arm has :been changed itc the position yit possessesduring lthe grinding operation, and one of fthe various possible'angular .settings has been 'made the `fixture. lAlso shownis'aportionof the grinding machinesfabrasive 'wheel in vone initialiposition relvactive.toithetoollbeingground;

Fig-Sis avertical crossfsectiontaken along line v3 3 of Fig. 2 to showhow a roller is positioned in :thexturesiangle-plate;

4 isfa vertical cross sectiontaken'along line y"Ilm-"li of Fig. "2,rshowing the'engagernent `between .the flxturesvise basefandiits'viseblock;

lFig. k5 is 'an end-view as seen from line '5e-@5 =of Fig. `2. Forsimplicity of drawing, the angular setting shown in Fig. 2 hasfbeenremovedfand'one of 'the fother possible angular ksettings has been.ma/de;

Fig. 56 lis fa longitudinal vertical section 'taken alongiline 1TB- "5of Fig. 1 .itc-show the internalcon- 'struction ofimy novel fixture;Fig. '7 is a vertical cross lsection ltaken along .line 1 1 of Fig.`6,showlingthepivotal connection between the iixtures lbase and angleplates, "and also the .attachment between the side plate and theangle-plate; and

lFig. l8r is a partial-perspe'ci-,ive viewshowingthe cutting edge of )anillustrative 4single point cutltingtool.

Essentiallymy xturewill beissen to consistfof a base plate II, an angleplate I2, a slide plate I3, a vise base I4 and a vise block I5. Otherelements, accessory to these major components just named, are employedand will be discussed in connection therewith.

The base plate Base plate II is shown in Figs. 1, 2 and 5 to 7. Viewedfrom above (see Fig. 1), the base plate is substantially rectangular inarea and is provided withfmounting vlugs I6, pivot lugs I'I, and settingarms I8. The base plate is also provided with a bevel .I 9 (see Figs. 5and 6).

Mounting lugs I6 (see Figs. 1, 2, 5 and 7) pro- Liect horizontally fromopposite sides of the base plate. Each lug is provided with an open endslot 20 which accommodates a T bolt 2I by means of 'which the fixture issecured to the Work table K22 of a simplegrinding machine. Aiding thisattachment are washers 23 and nuts 24 (one each of which is shown inFigs. 1 and 2) Pivot vlugs I'I are shown in Figs. 1, 2, 5 and 7. Theyproject upwardly from oneend of base plate I I and are in opposed,spaced relationship to each other.

Setting arms I8 (see Figs. 1, 2,5 and 7) are securedto base plate II bymeans of the shoulder screws 25 about which they are free to pivot. Theopposite end of each setting arm is provided with a slot 26 whosepurpose :will become apparent later.

Bevel l9,shown in Figs. 5 and', extends across the `base plates'uppersurface between pivot lugs "I-I and slopes downward from Vthe bases topsurface. Its purpose is to vprovide space to accommodate angle plate-I2,described below, when that plate is set atan angle to base plateIll.

vThe angle plate Angleplate fI2 is shownin Figs. 1 to 3 and 5 to '1. Asviewed from above (see Fig. 1) the angle plate consists of fa wideportion'2'1 having the beveled end 28 and a stepped down, narrowerportion j29. Wide portion 2I is slightlyless in dimension than the widthof baseplate I I `so that a space l5 exists between the two parts oneach side of the xtures longitudinal center line` Narrower portion 29 ofthe angle lplate ts into the space between mounting lugs AIt of Vbaseplate I'I so that limited angular adjustment between the base plate andthe angleplate'ismossibla as will be explained later. Other elements ofthe angle plate lare an open-end, shoulderedstud slot 30, a rollerrecess'3 I, a roller 32,'a'roller pin 33, a roller pin recess 34, anL-shaped stop bar '35, a closure bar 36, a threadedstudl, a-lock nut 38,ashoe rod 39, a shoe 40,.a spring 4I, the pivots Ii2, and .the .thumbscrews B3.

Open-end-.s'houldered stud .slot 3l) is kshown in Figs. 1, 6 and f7.lItislocated substantially midway between the angle platessides (seeFigs. 1 and 7) 'and extends `-lengthwise of .the `platefrom left toright (see Fig. 6). Near itsiower extremity isa shoulder 44.

Roller recess 3| (see Fig. 6) is likewise located substantially :midway-between the angle plates sides just adjacent 'the .-innerfend-ofshouldered stud slot 30. Roller 32 'is mounted in the recess by-me'ansof roller pin :33 llocatedwithin therollerpin recess 34 '(see Figs.Z-and 3) and is. secured there by means of set screws 46 v(-see Fig. 3).

.Theaxis of rollerpin 33'is`parallel to the angle plates yupper-andlower surfaces, and .is lso positioned lthat :the lower extremity off-roller 32 'extends somewhat below the lower surface of angle plate I2(see Figs. 2, 3, 5 and 6) L-shaped stop bar 35, having a free end 53, isshown in Figs. 1, 2, 3 and 6. It is secured to beveled end 28 of angleplate I2 by means of screws 41 (one of which is shown in Fig. 1) so thatan appreciable space 48 exists vertically between it and the top surfaceof the angle plate as shown in Figs. 2 and 6.

Closure bar 36 is shown in Figs. l, 2, 5 and 6. It is secured to angleplate I'2 across shouldered stud slot 30 by means of screws 49 (seeFigs. 1 and 5). .Passing through the closure plate in 'alignment withshouldered stud slot 30 is threaded adjusting stud 31 which isadjustably secured in position by lock nut 38. y

. Shoe rod 39 is shown in Figs. 1, 2, and 5 to '7. This rod is slidablysupported within threaded adjusting stud 31 and is threadedly attached,at its inner end, to shoe 40 (see Figs. 6 and '1).

Spring 4I, which is shown in Figs. 6 and 7, fits aroundrod 39 and isconiined between shoe 40 and threaded stud 31. By this arrangement theshoe is constantly urged toward the closed end of shouldered stud slot30.

Pivots 42 are shown in Figs. 2 and '1. They are located opposite eachother in appropriate recesses near the angle plates left end (see Fig.2). The pivots, about which the angle plate is free for limitedrotation, connect angle plate I2 to base plate I I to which they aresecured by means of set screws located in pivot lugs I1 (see Fig. '1).The congruous axes of the pivots are so located in relation to the lowersurface of the angle plate that in the Fig. 6 position the angle plateand the base plate are parallel.

In addition, the distance between the axes of pivots 42 and roller pin33 is such a dimension (preferably 4.000") so that angular settingbetween base plate II and angle plate I2 will be facilitated. Forexample (referring to Fig. 2), insertion of a certain thickness of gageblock |21 between roller 32 and base plate I I will establish a certainspecicangular relation between the base plate and the angle plate. Otherangles can be established by the use of other appropriately sized gageblocks.

Thumb screws 43 are shown in Figs. l, 2, 5

vand '1. These screws slidably t through slots 26 in setting arms I8 andthread into opposed,

The slide plate Slide plate I3 is shown in Figs. l, 2- and 5 to '7. Asviewed from above (see Fig. l) it is oblong in shape having a roundedend and a blunt end `56. Attached to the slide plate are a wear'platev51, a cylindrical shouldered stud 58, a vise base I4, a template stud60, and a template 6I.

Wear plate 51, shown in Figs. 2 and 5 to 7, is substantially identicalin area to slide plate I3 and is attached to its under surface by meansof screws 62 (one of which is shown in Fig. 6).

' Cylindrical shouldered stud 58 is shown in Figs. 6 and 7. It passesthrough an accommodating opening in wear plate -51 and is secured to theslide plates lower surface by means of screws 63 and dowels 64 (one eachof which is shown in portion of stop bar 35 parallel therewith.

Vise base I4, although an adjunct of slide plate I3, will'be describedlater under a separate heading.

Template stud 60 is shown in Figs.v 1, 2 and 6.

It is press-fitted intslide plate I3 directlyabove the center ofshouldered stud 58, and projects somewhat above the slide plates uppersurface to serve as a means of locating the various interchangeabletemplates whichrnay be used on the fixture.

Template 6I appears in Figs. l, 2 and 6. The template, which is made ofplate stock, has a slot -61 and a shaped end 68. This template is one ofa number usable on my fixture and having variously shaped ends,depending upon requirements for the tools to be ground.' Slot 61 (seeFigs. 1 and 6), in conjunction with template stud 60, locates thetemplate upon slide plate I3 to which it is secured by means of screws69. The templates shaped end 68 (see Fig. l) conforms to the shape of acutting edge that it is desired to grind upon a tool, but for practicalpurposes it is desirable to make the shape on the template approximatelyone inch larger all aroundV than the actual size of the tools cuttingedge Ato be ground. In this way, templates are more easily and moreaccurately made.

As shown in Fig. 6, shaped end 68 of template 6I is constantly urgedagainst free end 53 of stop bar 35 through theaction of spring 4Iagainst shoe 40, cylindrical shouldered stud 58, and slide plate I3.Moreover, the slide plate is capable of independent or simultaneousoscillatory or sliding motion in relation to angle plate I2 so that thetemplates shape is reproduced on the tool being ground.

The vise base Vise base I4 is shown in Figs. 2 and 4 to '7. As viewedfrom above, the vise base has the same shape as vise block I5 (seeFig. 1) later to be described. In other words, vise base I4.iscylindrical having oppositely located parallel flats 12 and 13 whichextend from top to bottom (see Figs. 2, 5 and 6). Also to be consideredin connection with the vise base are the upper arcuate end 14, thearcuate groove 15, the arcuate slot 16, the pointed indicator 11, theflat lower end 18. and the operating vhandle-19.

Upper arcuate end 14 of vise base I4 is shown in Figs. 2,- 5 and 6. Thisend is arcuately shaped about an axis (not shown) which lies parallel tolower fiatv end 18 in an imaginary plane that perpendicularly bisectsflats 12 and 13.

Arcuate groove 15 (shown in Figs. 2- and 4 to 6) vis also generated inthe vise bases upper end about the same axis, so that the groove isconcentricto upper arcuate end 14 and is also parallel to flats 12 and13. s

Arcuate slot 16 which extends between flat 12 and arcuate groove 15 (seeFigs. 5 and 6) likewise is generated about the same axisl so that italso is concentric to upper arcuate end 14.

Pointed indicator 11 is shown in Figs. 5 and 6'. It is located in anaccommodating groove in fiat 12 where it is secured by means of a screw80.

9 Operation The operation of my novel fixture is exceedingly simple andis performed in the manner now to be described. For our present purpose,the grinding machines abrasive wheel |28 is represented in Figs. 2 and5. The wheel, which may be' either of the disc or cuppedl type, issecured to the machines spindle |29 by means of a washer |39 and a nut|3|. It shall be assumed that a tool, preferably one of a number of liketools, is to be ground for a certain job, and that no template is on theiixture. First, the particular template for the tool and/ or tools to beground is positioned about locating stud 69 and secured l to slide plateI3 by means of screws 69 (see Figs. 1, 2 and 6) By positioning`adjusting knob |22 and lock knob |23, locating bar |24 is placed sothat its inside face |26 is approximately one inch from the end 53 ofstop bar 35. When so positioned, lock knob |23 is tightened againstadjusting knob |22 thereby securing the adjustment.

The tool to be ground is placed in tool groove 92. While manuallyholding locating bar |24 in its path, the tool is pushed toward thelocating bar until the edge of the tool abuts the bar as shown in Fig.l. From the bracket side of the tool groove, the tool is packed out bymeans of spacer |02 until the center of the radius of the tool issubstantially in alignment with the center of the radius of thetemplate. Set screws 93 are then tightened, securing the tool inposition for grinding.

Information supplied by the tool designer will specify just what theIangular settings of angle plate I2 and the vise block I5 should be. Thesetting of the angle plate is obtained in Well known fashion by placinga speciied gage block |27 between roller 32 and base plate (see Fig. 2).Roller 32 greatly facilitates such placement and removal of the gageblock, and minimizes wear on both the gage block and the parts contactedthereby. When the angle is set thumb screws 43 are tightened to securethe setting. The setting of vise block is accomplished by tilting it therequired amount to the left or right (see Fig. 5) as indicated bygraduations 9|. When set, the position is secured by means of clamp nut99.

The xture is then secured in conventional manner to the table 22 of asimple grinding machine by means of T bolts 2|, washers 23, and nuts 24(one of each of which is shown in Figs. l and 2).

In order to get the proper relationship bey tween the grinding machinesabrasive wheel |28 and my novel xture, the grinders work table 22 isadjusted by well known means toward or away from the wheel untilconta-ct between the wheel and tool ||l| is just made (see Figs. l, 2,5). The work table is then moved longitudinally away from the machinesgrinding wheel until the end of the tool is free of the wheels face. Thework table is then adjusted the preferred depth of grind closer to thegrinding wheel which, in the meantime, is caused to rotate.

Work table 22 carrying fixture and tool is moved longitudinally backtoward the grinding wheel. As the tool and wheel make contact, andgrinding is started, the central position of the slide plate ispreserved by maintaining a hold on operating handle 19. The table is fedacross the wheel until the tool is approximately vertically beneath thewheels center. Longitudinal l0 movement of the table is then stopped andoperating handle 19 is oscillated so as to cause template 6| to movepast stop bar |24. As a result, the tool is made to follow a pathequivalent to the shape of the template, valthough on a smaller scale,as the cutting edge is being ground.

The workA is then moved longitudinally away from the wheel, and theground tool is removed. The iixture is -reloaded withv another tool andthe process isrepeated.V Y

ThoseY skilled in the art realize that many modifications and variationsof my inventive device are possible without departing from its-originalspirit and scope. For that reason, I do not wish to be limited by thenarrow confines of the single practical embodiment here disclosed anddes-cribed for illustrative reasons only, but instead only by the claimsappended hereto. Y

From the foregoing it will be apparent that I have provided a small,compact grinding fixture which is capable of simultaneous compoundangular adjustment and separate or combined curvilinear or rectilinearmovement; that I have provided a grinding xture which can be used on themost simple type of grinding machine; and that I have provided agrinding fixture which will eliminate the necessity for multiple set-upsof a single machine, or the need for more than one machine in formingdesired proles on cutting tools.

' I claim:

l. In apparatus for grinding of profiles and clearances therefor onsingle point cutting tools, the combination of a rotatable grindingwheel, a work table adjacent to said grinding wheel and positionallyadjustable with respect thereto, a fixture base mounted on said table,an angle plate pivotally mounted on said xture base so as selectively.toform different angles therewith, means for maintaining said angle plateat any desired angle with respect to said fixture base, a stop barsecured to said angle plate, a slide plate mounted on said angle platefor pivotal rotation about a perpendicular to the face of said angleplate and for sliding movement toward and away from said stop bar, atemplate removably secured to said slide plate and having a proleconforming to that desired to be ground on a cutting tool, resilientmeans constantly ur-ging said slide plate and template thereon in thedirection of said stop bar so'that said templates profile is constantlyabutting the stop bar, a vise -base mounted on said slide plate andhaving an upper arcuate extremity, a vise block for supporting the toolto be ground and having an arcuate lower extremity which is matinglyengageable with the upper arcuate extremity of said base base atdiiierent angular positions in a plane perpendicular to the face of saidangle plate, a locating bar attached to said vise block and removablypositionable for use in setting the tool to be ground the properdistance from said stop bar, and an operating handle secured to saidvise base, whereby oscillatory movement applied to said handle causesmovement of the slide plate from side to side, forward and backward asdiiferent portions of the templates profile push against the stop bar,thereby causing the tool to move into contact with said grinding wheelalong a path conforming to the proiile of the template and at a compoundangle caused by the angular settings of the angle plate and the viseblock.

2. A tool shaping fixture comprising, a base plate, an angle platehaving a stop bar and bel 1 ine'. supportable in seriousAangular-relationships tmsaidgbasez plate', as slide; plate keyed;y tosaid angleplate ion pivotal rotation within al. preselected limi-tedarea' aboutv a perpendicular to4 the; face of saidangle plate-a templateremovably secured tdsaidslide plate and havinga prole"eonfmsnt ing tothat desired to be ground cn a. cutting tool, resilient` meansconstantly urging said, slide1 plate andi template thereon the'direction, ofY said stop bar ses that, said', teni-platesl profile; isconstantly abutting the stop loer, a, vise base carried betisaieslideYplate and having an arcuate free end-mvise'block for supperting atooltozbefshaped and; having', an arcuate endi for mating engage*- with;the arcuatefree end; of said base, scale'andzpointer meansrforindicating thellateral displcement ol said.: vise base with respect. tosmidtviseblock, andarrollerrmountedm saidi angle plate so that a.;pertiongo the.` roller surface constanthl: protrudes from the.plateslower surface tproivide a'xex reference line for-determixnng I2 bymeans of a standardigage block the angular distance between the angleplate and said base plete,l the namedelements cuoperating to" makepossible-the uniform supportingof successive 'tools to be shaped atacompound angle'. caused by the angular settings of the angle* plate withrespect to' said base plate and oi` thevisenbloclt with reespect to saidvise; base, and to, move tools-A. thus supported alongA a,A path, whichconforms tu the shape of the templates profile.

JOSEPH J; SANDERS:

REFERENGES CITED The following'. references are of record` m the fileyof.' this patent.:

UNITED STATES PATENTSy Number Name Date 1,255,962 Warner et al. Feb;12',.l:9'l8 20 2,375,619 Bum Mazy 19245 ZAIEHSG Mader July'12g`l9'49

